You can try 'Case Math' on the iOS store.
Magoosh's mental maths app, Mental math cards challenge app would be also useful.
In general, to practice your quantitative skills I would recommend different math, logic, and verbal tests on https://trytalentq.com/how-to-prepare/# and then select "Elements Practice Test".
You don´t need to learn them by heart, rather skipping through to get a first impression and a better understanding.
If you need any further help or career advice, feel free to reach me out.